Heretofore, various electrical connectors and in particular snap fit type electrical connectors are known for connecting electrical wire or cables to an electrical box. Such known snap fit electrical connectors or adaptors have been made the subject of prior U.S. Patents, for example, U.S. Pat. Nos. 1,483,218; 2,744,769; 5,171,164; 5,373,106; 6,114,630; 6,383,439; 6,521,831 and other patents.
Generally, such known snap fit connectors or adaptors are formed of a spring steel material having a circular configuration which is less than a full circle whereby the resiliency of the spring steel under force enables the circular adaptor to expand and contract. Such known snap ring connectors or adaptors are generally provided with outwardly bent grounding tangs arranged to engage the internal periphery of a knock out hole of an electric box or panel. In the operative position of such prior snap fit connectors or adaptors, the trailing edge of the grounding tangs is biased so as to engage the inner periphery or surface of the knockout hole. As such grounding tangs are angularly bent outwardly relative to the plane or axis of the electrical connector or adaptor, the edge of such grounding tangs make only a line contact with the internal periphery or surface of the knockout hole. As a result, only a small surface contact and minimal grounding effect is achieved.
Despite the extensive background relating to electrical connectors, and in particularly those utilizing snap fit adaptors for effecting a snap fit connection to an electrical box or panel, continuing efforts are being made to improve, modify and/or enhance the operability and/or the efficiency of such electrical connectors or adaptors to advance the electrical connector art.
One such improvement is the recently developed frustro-conical shaped snap fit connector or adaptor as described in U.S. patent application Ser. No. 12/006,946, filed Jan. 8, 2008, which is herein incorporated by reference, and was granted as U.S. Pat. No. 7,723,623. Therein, disclosed is a snap fit connector or adaptor provided with grounding tangs that are coincidental or flush with the slope of the frustro-conical plane or surface of the adaptor. As the frustro-conical plane of such adaptors slope radially outward from the leading edge to the trailing edge thereof, the arrangement of the grounding tangs is such that in its operative or working position, the trailing edge of the frustro-conical shaped snap fit connectors or adaptors also functions as a grounding tang that make only a line contact with the internal periphery of a knock out hole.
While the recently developed frustro-conical shaped snap fit connector or adaptor has improved the efficiency of making cable and wire connections to electrical boxes there is a continuing demand for improvement. In particular there is a need to provide improved and enhanced grounding of electrical boxes and connectors.